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arXiv · 1010.5876

Chiral symmetry of graphene and strong coupling lattice gauge theory

Yasufumi Araki·Tetsuo Hatsuda
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Abstract

We model the electrons on a monolayer graphene in terms of the compact and non-compact U(1) lattice gauge theories. The system is analyzed by the strong coupling expansion and is shown to be an insulator due to dynamical gap formation in/around the strong coupling limit. This is similar to the spontaneous chiral symmetry breaking in strong coupling gauge theories. The results from the compact and non-compact formulations are compared up to the next-to-leading order of the strong coupling expansion. Excitonic modes and their dispersion relations in the insulating phase are also investigated: it is found that there arises a pseudo-Nambu--Goldstone mode obeying the Gell-Mann--Oakes--Renner type formula.

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Yasufumi Araki, Tetsuo Hatsuda. 2010-10-28. Chiral symmetry of graphene and strong coupling lattice gauge theory. https://arxiv.org/abs/1010.5876

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